Gymnastic apparatuses such as pommel horses are typically covered with leather covers. Because such covers are usually somewhat slippery when new, they are typically conditioned by roughening with scouring pads, wire brushes, knives, etc. Scouring is typically done by hand with a circular motion resulting in a visible pattern of swirls on the surface. Conditioning in this fashion entails cutting and gouging the surface of the cover, tending to result in shortened life of the cover, making it necessary to have the apparatus recovered periodically.
Gymnasts frequently apply chalk to their hands when practicing and during performances. This chalk builds up on the cover of the apparatus, filling in the texture and leaving a smooth, somewhat hard surface that must be brushed or sanded to remove the chalk. Because of the pattern of swirls and rough texture of a hand-conditioned cover, it is difficult to remove chalk as desired. In addition to chalk, such substances as KARO Brand Corn Syrup, pine tar, and spray adhesive are sometimes used by gymnasts to improve their grip to conventional covers.
In light of these conditions, conventional gymnastic apparatus covers, which cost several hundred dollars, may wear out after relatively short periods, presenting substantial costs to schools and other gymnasium operators. Also, surface conditioning practices and uneven wear may impart substantially non-uniform characteristics to a cover, presenting potentially unsafe conditions to a gymnast as seemingly similar portions of a cover may exhibit substantially different properties. In some cases, falls may lead to serious injuries such as broken bones and paralysis. The need for higher grip surfaces for gymnastics apparatuses has been known for a long time.
Because the handles of many tools, mallets, racquets, golf clubs and sport sticks have leather grips, some of the same problems associated with the use of leather covers for gymnastic apparatuses are also encountered during use of these handles. For example, the leather grips can be slippery when new. Perhaps more importantly, the leather grips tend to become impregnated with perspiration during use of the grips, causing the grips to become more slippery with increasing use. Of course, this can result in reduced gripping of the handle and a consequent drop in safety and performance potential. For this reason, users of leather gripped handles often apply chalk or tacky substances to the grips to improve their gripping. The repeated cycles of impregnation of the leather grip with perspiration and subsequent drying in the periods when the grip is not being used, combined with natural aging, result in rapid drying of the leather grip, which loses its softness and must be replaced. Further, if chalk or tacky substances are applied to the leather grip, there may be a tendency for these materials to build up on the grip and further reduce the life of the grip.
In light of the above drawbacks associated with the use of leather grips, some people have substituted rubber or plastic grips for the leather grips. These substitute grips have some advantages over leather grips since they tend to resist perspiration impregnation, can be easier to dry, may not age as quickly, and may be washable. However, the need for better gripping characteristics has remained.
U.S. Pat. No. 3,585,101 (Stratton et al.) discloses a material comprising a film having a knurled pattern, e.g., a series of ridges, on one surface and an adhesive layer on the opposite surface. U.S. Pat. No. 4,488,918 (Jofs) discloses a plastic film having a non-slip surface comprising spaced random patterns of rigid peaks and ridges formed of a second thermoplastic layer coextruded with and bonded to the plastic film. European Patent Application No. 81830005.5, Publication No. 033,301 (Gibello) discloses handle coverings for tennis racquets and the like which comprise sleeves with relief patterns for a good grip. U.K. Patent No. 2,057,894 (Sasaki) discloses a tape for grips of game and sports appliances, e.g., racquets.